Crane for extracting horizontal long tube bundles

ABSTRACT

This disclosure teaches a hydraulic crane for removing a horizontal long tube bundle along with its tube sheet from its shell. A winch line, connected to the tube sheet, extracts the tube bundle. The crane has a boom comprising a proximal and a distal section mounted in telescoping relationship. The distal section has a boom point with a pair of hoisting slings depending therefrom to support the tube bundle as it is being extracted from the shell. A pulley suspended from the proximal section aligns the winch line in horizontal orientation. The hoisting slings are spaceable apart sufficiently so that they span a major portion of the length of the tube bundle whereby the tube bundle can be suspended and balanced safely.

United States Patent [19] Murphy Oct. 16, 1973 [76] Inventor: Thomas v. Murphy, 1026 Morago Dr., Bel-Air, Calif. 90049.

[22] Filed: Aug. 16, 1972 [21] App]. No.: 280,966

4/1972 Murphy 2l4/l P Primary Examiner-Gerald M, Forlenza Assistant Examiner-Frank E. Werner Attorney-Charles E. Baxley [57] ABSTRACT This disclosure teaches a hydraulic crane for removing a horizontal long tube bundle along with its tube sheet from its shell. A winch line, connected to the tube sheet, extracts the tube bundle. The crane has a boom comprising a proximal and a distal section mounted in telescoping relationship. The distal section has a boom point with a pair of hoisting slings depending therefrom to support the tube bundle as it is being extracted from the shell. A pulley suspended from the proximal section aligns the winch line in horizontal orientation. The hoisting slings are spaceable apart sufficiently so that they span a major portion of the length of the tube bundle whereby the tube bundle can be suspended and balanced safely.

1 Claim, 1 Drawing Figure BACKGROUND OF THE INVENTION This invention relates to petroleum refineries, chemical plants and other similar installations which include among their equipment horizontal long tube and shell assemblies. Maintenance operations require extracting tube bundles from their shells for inspecting, repairing and/or cleaning the assemblies. As a tube bundle is extracted, its weight and inherent lack of flexural strength cause substantial deflections which can result in damage to the tubes and their connections. One prior method for extracting horizontal long tube bundles was to employ a horizontal hoist and two cranes. Accordingly, extracting such tube bundles by that method required three pieces of equipment with three operators and other personnel to coordinate operations. Unless the extracting technique was carried out with extreme precision, damage to tubes and connections resulted. Another prior method taught in my US. Pat. No. 3,658,191 was to use a hydraulic crane with at least two movable boom sections.

SUMMARY OF THE INVENTION The present invention copes with extracting horizontal long tube bundles from their shells in a novel and facile way. A hydraulic crane is provided with a boom comprising a proximal section and a single distal section mounted in telescoping relationship. The distal section is provided with a boom point having a pair of hoisting means. A pulley is suspended from the proximal section for alignment of a winch line in horizontal orientation. As a tube bundle is extracted from its shell by means of the winch line, the two hoisting means with suitable slings support the tube bundle at points spaced sufficiently along its length so that the bundle is suspended therefrom. Accordingly, one object of this invention is to permit extracting of horizontal long tube bundles from their shells using a single item of equipment.

A further object of this invention is to improve horizontal orientation of the winch lines used to remove the tube bundles.

A still further object of the invention is to permit use of a hydraulic crane which is simpler, less expensive and more rugged than those which have been used heretofore in this service.

A still further object of this invention is to permit extraction of horizontal long tube bundles without damage to the tubes or their connections.

A still further object of the invention is to provide a crane of the characterstated which is self propelled and maneuverable whereby it is capable of reaching and working in relatively inaccessible locations of plants.

A still further object of the invention is to.provide a crane of the character stated which can balance and suspend tube bundles between slings which are spaced apart, pick up, swing and transport the bundles for placement on a platform, truck or other vehicle so that the bundles can be removed easily to another area for inspecting, cleaning and/or repairing them.

A still further object of the invention is to provide a crane of the character stated which is capable of conventional service when not being used for extracting tube bundles.

DRAWING The foregoing and other features of the invention will be seen more fully from the following detailed descrip tion of a preferred embodiment taken in conjunction with an accompanying drawing of a crane according to this invention shown in the operation of extracting a horizontal long tube bundle from its shell.

PREFERRED EMBODIMENT Tube and shell assemblies are very popular for such services as heat exchangers, condensers and the like and this type of assembly finds wide application in petroleum refineries and chemical plants as well as in other similar installations. Pressure drop, efficiency of heat transfer, economy and structural considerations generally favor horizontal long tube and shell assemblies with U-shaped tubes engaged in sealed relationship with tube sheets for passage of a tube-side fluid therethrough. A head is generally engaged in sealed relationship with a tube sheet and accommodates introduction and removal of the tube-side fluid to and from the U-shaped tubes. A shell-side fluid enters and leaves via openings provided in the shell.

To facilitate inspecting, repairing and cleaning; tube and shell assemblies are designed for extracting the tube bundle along with its tube sheet from the shell. Toward this objective, the head is usually removable and upon its removal, the present invention comes into play. As shown in the drawing, shell and tube assembly 1 has shell 2, intermediate floating tube supports 3 and end tube sheet 4 to which ends of U-shaped tubes 5 are connected in sealed engagement. The assembly is also provided with a head (not shown) for introducing and removing tube-side fluid. Intermediate tube supports 3 are extracted along with end tube sheet 4 and tubes 5, but intermediate tube supports 3 present no particular problem. However, it should be noted here that loss of support from intermediate tube support 3, experienced when a tube bundle 5 is extracted, increases the unsupported span of tube bundle 5 thereby aggrevatin g deflections which bundle 5 undergo and giving rise to danger of tube bundle 5 getting hung up or having tubes 5 or connections between tubes 5 and end tube sheet 4 damaged.

Crane 6 is known as a hydraulic crane and its general design is well known, except for modifications according to the present invention. Crane 6 is self propelled with four wheel drive and four wheel steering. Boom 7 is mounted on body 8 of crane 6 by means of shippers 9 and turntable 1 l and is comprised of proximal section 12 and distal section 13 mounted telescopically. To regulate boom length, proximal section 12 is provided with a hydraulic ram for projecting distal section 13 therefrom a desiredamount. The hydraulic ram for regulating boom length is of conventional design and operation. Boom 7 also may be provided with jib l4 and swing line 15 with headache ball 16.

It is desired to accommodate extraction of tubebundles 5 from their shells 2 which may be at various elevations. Tube bundles 5 are extracted by winch 17 mounted on body 8 connected by winch line 18 over pulley 19 to end tube sheet 4 by means of eye bolts'20. Suspension of pulley 19 from proximal section 12 of boom 7 and regulation of the elevation'of pulley 19 assures that winch line 18 pulls horizontally.

Tube bundle 5 must be supported at at least two points along its length. For this purpose boom point 21 is provided with slings 22 and 23 suspended from hookblocks 24 and 25 respectively. Lifting mechanisms of known design are connected operatively to hookblocks 24 and 25 respectively. In order to support tube bundle 5 as it emerges from shell 2, sling 22 encircles tube bundle 5 at 26, is connected to hookblock 24 and is suspended by means of its associated lifting mechanism. Distal section 13 of boom 7 is drawn into proximal section 12 as Winch 1'7 extracts tube bundle 5. When a major portion of tube bundle 5 is out of shell 2, sling 23 encircles tube bundle 5 at 27, is connected to hookblock 25 and is suspended by means of its associated lifting mechanism. On clearing shell 2, crane 6 has tube bundle 5 balanced in suspension from slings 22 and 23 so that tube bundle 5 can be turned, transported, lifted and/or lowered to a platform, truck or other vehicle for being moved to another area where it may be worked on with convenience.

It will be understood by those familiar with rigging and lifting or those familiar with cranes, that wide deviations may be made from the preferred embodiment of the invention described herein without departing from the main theme of invention set forth in the following claim.

I claim:

1. A crane for extracting horizontal long tube bundles, comprising a tube sheet with U-shaped tubes connected thereto, from a shell and comprising in combination:

a body provided with means for driving and maneuvering the body,

a boom mounted on the body and comprising a proximal section near the body and a distal section remote from the body,

the distal section mounted telescopically within the proximal section,

boom-length regulating means for moving the distal section relative the proximal section,

a winch mounted on the body and connectable by means ofa winch line to the tube sheet for extracting the tube sheet and the tube bundle from the shell,

a pulley suspended from the proximal section and the winch line passing over the pulley for maintaining horizontal orientation of the winch line,

a boom point mounted on the distal section remote from the body and provided with a first and a second hoisting means,

a first sling arranged for embracing the tube bundle and attached to the first hoisting means to provide a first support for the tube bundle as it is extracted from the shell,

a second sling arranged for embracing the tube bundle and attached to the second hoisting means to provide a second support for the tube bundle as it is extracted further from the shell,

the first and second slings spaced apart sufficiently to span a major portion of the length of the tube bundle. 

1. A crane for extracting horizontal long tube bundles, comprising a tube sheet with U-shaped tubes connected thereto, from a shell and comprising in combination: a body provided with means for driving and maneuvering the body, a boom mounted on the body and comprising a proximal section near the body and a distal section remote from the body, the distal section mounted telescopically within the proximal section, boom-length regulating means for moving the distal section relative the proximal section, a winch mounted on the body and connectable by means of a winch line to the tube sheet for extracting the tube sheet and the tube bundle from the shell, a pulley suspended from the proximal section and the winch line passing over the pulley for maintaining horizontal orientation of the winch line, a boom point mounted on the distal section remote from the body and provided with a first and a second hoisting means, a first sling arranged for embracing the tube bundle and attached to the first hoisting means to provide a first support for the tube bundle as it is extracted from the shell, a second sling arranged for embracing the tube bundle and attached to the second hoisting means to provide a second support for the tube bundle as it is extracted further from the shell, the first and second slings spaced apart sufficiently to span a major portion of the length of the tube bundle. 